@import url('https://fonts.googleapis.com/css2?family=Press+Start+2P&family=VT323:wght@400&display=swap');

/* =====================
   CSS 变量 & 重置
   ===================== */
:root {
  --c-black: #000000;
  --c-white: #ffffff;
  --c-border: #000000;
  --c-bg: #ffffff;
  --c-text: #000000;
  --c-accent: #000000;
  --c-muted: #555555;
  --c-surface: #f5f5f5;
  --c-hover-bg: #000000;
  --c-hover-text: #ffffff;

  --font-pixel: 'Press Start 2P', monospace;
  --font-mono: 'VT323', monospace;
  --font-body: system-ui, -apple-system, 'Segoe UI', sans-serif;

  --radius: 28px;
  --border: 2px solid var(--c-border);
  --nav-h: 64px;
  --max-w: 1200px;
  --content-max: 760px;
  --transition: 220ms cubic-bezier(.4,0,.2,1);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--c-text);
  background: var(--c-bg);
  overflow-x: hidden;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

ul, ol {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

/* =====================
   页面外壳
   ===================== */
.page-wrapper {
  display: grid;
  grid-template-rows: auto auto 1fr auto;
  min-height: 100vh;
}

/* =====================
   导航
   ===================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--c-black);
  border-bottom: var(--border);
  height: var(--nav-h);
}

.main-nav {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  gap: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex: 1;
  overflow: hidden;
}

.nav-links a {
  color: var(--c-white);
  font-family: var(--font-pixel);
  font-size: 0.45rem;
  letter-spacing: 0.02em;
  padding: 0.5rem 0.6rem;
  border-radius: 6px;
  white-space: nowrap;
  transition: background var(--transition), color var(--transition);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  background: var(--c-white);
  color: var(--c-black);
  outline: none;
}

.nav-brand {
  font-family: var(--font-pixel);
  font-size: 0.7rem;
  color: var(--c-white);
  margin-right: 0.75rem;
  flex-shrink: 0;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}

.nav-brand-text {
  font-size: 1.2rem;
  font-weight: 900;
  border: 2px solid var(--c-white);
  border-radius: 8px;
  padding: 0.2rem 0.5rem;
  line-height: 1;
}

.nav-logo {
  height: 36px;
  width: auto;
}

.nav-hamburger {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 8px;
  border-radius: 8px;
  flex-shrink: 0;
  margin-left: 0.5rem;
  transition: background var(--transition);
}

.nav-hamburger span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--c-white);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav-hamburger:hover {
  background: rgba(255,255,255,0.15);
}

.nav-hamburger[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-hamburger[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}
.nav-hamburger[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav-cta {
  flex-shrink: 0;
  margin-left: 0.75rem;
  font-family: var(--font-pixel);
  font-size: 0.42rem;
  color: var(--c-black);
  background: var(--c-white);
  border: 2px solid var(--c-white);
  border-radius: 8px;
  padding: 0.5rem 0.9rem;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  transition: background var(--transition), color var(--transition);
  white-space: nowrap;
}

.nav-cta:hover,
.nav-cta:focus-visible {
  background: transparent;
  color: var(--c-white);
  outline: none;
}

/* =====================
   全屏遮罩菜单
   ===================== */
.fullscreen-menu {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: var(--c-black);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  opacity: 0;
  pointer-events: none;
  transform: scale(1.04);
  transition: opacity 240ms ease, transform 240ms ease;
}

.fullscreen-menu.is-open {
  opacity: 1;
  pointer-events: auto;
  transform: scale(1);
}

.menu-close {
  position: absolute;
  top: 1.25rem;
  right: 1.5rem;
  color: var(--c-white);
  font-family: var(--font-pixel);
  font-size: 1rem;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--c-white);
  border-radius: 8px;
  transition: background var(--transition), color var(--transition);
}

.menu-close:hover {
  background: var(--c-white);
  color: var(--c-black);
}

.menu-nav {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  padding: 2rem;
}

.menu-link {
  font-family: var(--font-pixel);
  font-size: 0.7rem;
  color: var(--c-white);
  padding: 0.75rem 1.5rem;
  border: 2px solid transparent;
  border-radius: 12px;
  min-height: 48px;
  display: flex;
  align-items: center;
  transition: border-color var(--transition), background var(--transition);
  text-align: center;
}

.menu-link:hover,
.menu-link:focus-visible {
  border-color: var(--c-white);
  background: rgba(255,255,255,0.1);
  outline: none;
}

/* 菜单动画 stagger */
.fullscreen-menu.is-open .stagger-item {
  animation: staggerIn 300ms ease both;
  animation-delay: calc(var(--i, 0) * 60ms + 80ms);
}

@keyframes staggerIn {
  from { opacity: 0; transform: translateY(16px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* =====================
   粘性锚点条
   ===================== */
.sticky-anchor-bar {
  position: sticky;
  top: var(--nav-h);
  z-index: 90;
  background: var(--c-black);
  border-bottom: var(--border);
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
.sticky-anchor-bar::-webkit-scrollbar { display: none; }

.anchor-bar-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.25rem;
  min-height: 44px;
}

.anchor-link {
  font-family: var(--font-pixel);
  font-size: 0.4rem;
  color: var(--c-white);
  padding: 0.4rem 0.7rem;
  border-radius: 6px;
  white-space: nowrap;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  transition: background var(--transition);
}

.anchor-link:hover {
  background: rgba(255,255,255,0.15);
}

/* =====================
   Hero（首页）
   ===================== */
.hero {
  position: relative;
  min-height: 70vh;
  background: var(--c-black);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.hero-inner {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 4rem 1.5rem 5rem;
  gap: 2rem;
  align-items: center;
  width: 100%;
}

.hero-media {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  border: var(--border);
  aspect-ratio: 4/3;
}

.hero-media .hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-placeholder {
  background: repeating-conic-gradient(#333 0% 25%, #111 0% 50%) 0 0 / 16px 16px;
  min-height: 280px;
}

.hero-content {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  text-align: right;
  gap: 1.25rem;
}

.hero-badge {
  font-family: var(--font-pixel);
  font-size: 0.45rem;
  color: var(--c-black);
  background: var(--c-white);
  border-radius: 6px;
  padding: 0.35rem 0.7rem;
  display: inline-block;
  letter-spacing: 0.05em;
}

.hero-title {
  font-family: var(--font-pixel);
  font-size: clamp(1rem, 3vw, 1.6rem);
  color: var(--c-white);
  line-height: 1.6;
  letter-spacing: 0.03em;
}

.hero-lead {
  font-size: 1rem;
  color: rgba(255,255,255,0.8);
  line-height: 1.7;
  max-width: 420px;
}

.hero-btn {
  font-family: var(--font-pixel);
  font-size: 0.5rem;
  color: var(--c-black);
  background: var(--c-white);
  border: 2px solid var(--c-white);
  border-radius: 12px;
  padding: 0.8rem 1.6rem;
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  transition: background var(--transition), color var(--transition);
}

.hero-btn:hover,
.hero-btn:focus-visible {
  background: transparent;
  color: var(--c-white);
  outline: none;
}

/* 斜切底边 */
.hero-cut {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: var(--c-white);
  clip-path: polygon(0 100%, 100% 100%, 100% 0);
}

.hero-cut-sm {
  height: 40px;
  position: relative;
  bottom: unset;
}

/* =====================
   页面头部（非首页）
   ===================== */
.page-hero-slim,
.about-hero,
.privacy-hero {
  background: var(--c-black);
  padding: 3rem 1.5rem 0;
  position: relative;
}

.page-hero-inner,
.about-hero-inner,
.privacy-hero-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding-bottom: 2.5rem;
}

.about-hero-inner {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2rem;
  align-items: center;
}

.about-hero-text {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.about-hero-media {
  flex-shrink: 0;
}

.about-hero-img {
  width: 200px;
  height: 200px;
  object-fit: cover;
  border-radius: var(--radius);
  border: var(--border);
}

.about-hero-deco {
  width: 160px;
  height: 160px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 3px solid var(--c-white);
  border-radius: var(--radius);
}

.pixel-deco {
  font-family: var(--font-pixel);
  font-size: 3rem;
  color: var(--c-white);
}

.eyebrow-tag {
  font-family: var(--font-pixel);
  font-size: 0.42rem;
  color: var(--c-black);
  background: var(--c-white);
  border-radius: 6px;
  padding: 0.3rem 0.6rem;
  display: inline-block;
  letter-spacing: 0.05em;
}

.page-title {
  font-family: var(--font-pixel);
  font-size: clamp(0.85rem, 2.5vw, 1.3rem);
  color: var(--c-white);
  line-height: 1.7;
  letter-spacing: 0.02em;
}

.page-lead {
  font-size: 1rem;
  color: rgba(255,255,255,0.8);
  line-height: 1.7;
  max-width: 680px;
}

.page-meta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.meta-date {
  font-family: var(--font-mono);
  font-size: 1rem;
  color: rgba(255,255,255,0.6);
  letter-spacing: 0.03em;
}

/* =====================
   主内容区
   ===================== */
.site-main {
  padding: 3rem 1.5rem 4rem;
}

.content-article {
  max-width: var(--max-w);
  margin: 0 auto;
}

.content-outer {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

.content-inner {
  min-width: 0;
}

/* FAQ & Privacy 双栏 */
.faq-outer,
.privacy-outer {
  grid-template-columns: minmax(0, 1fr) 260px;
  align-items: start;
}

/* =====================
   Prose 正文排版
   ===================== */
.prose {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--c-text);
}

.prose h1,
.prose h2,
.prose h3,
.prose h4 {
  font-family: var(--font-pixel);
  line-height: 1.6;
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  letter-spacing: 0.02em;
}

.prose h2 { font-size: clamp(0.75rem, 2vw, 1rem); }
.prose h3 { font-size: clamp(0.65rem, 1.5vw, 0.85rem); }
.prose h4 { font-size: 0.7rem; }

.prose p {
  margin-bottom: 1.25rem;
}

.prose ul,
.prose ol {
  margin-bottom: 1.25rem;
  padding-left: 1.5rem;
}

.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }

.prose li {
  margin-bottom: 0.5rem;
  line-height: 1.7;
}

.prose a {
  color: var(--c-black);
  border-bottom: 2px solid var(--c-black);
  transition: border-color var(--transition);
}

.prose a:hover {
  border-color: transparent;
}

.prose blockquote {
  border-left: 4px solid var(--c-black);
  padding-left: 1.25rem;
  margin: 1.5rem 0;
  color: var(--c-muted);
  font-style: italic;
}

.prose code {
  font-family: var(--font-mono);
  font-size: 1.1em;
  background: var(--c-surface);
  border-radius: 4px;
  padding: 0.1em 0.3em;
}

.prose pre {
  background: var(--c-surface);
  border: var(--border);
  border-radius: 12px;
  padding: 1.25rem;
  overflow-x: auto;
  margin-bottom: 1.25rem;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.25rem;
  font-size: 0.95rem;
}

.prose th,
.prose td {
  border: var(--border);
  padding: 0.6rem 0.9rem;
  text-align: left;
}

.prose th {
  background: var(--c-black);
  color: var(--c-white);
  font-family: var(--font-pixel);
  font-size: 0.55rem;
}

/* =====================
   侧边栏
   ===================== */
.faq-aside,
.privacy-aside {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  position: sticky;
  top: calc(var(--nav-h) + 1rem);
}

.aside-block {
  border: var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.aside-heading {
  font-family: var(--font-pixel);
  font-size: 0.5rem;
  letter-spacing: 0.05em;
  color: var(--c-text);
  padding-bottom: 0.5rem;
  border-bottom: var(--border);
}

.aside-link {
  display: block;
  font-size: 0.9rem;
  padding: 0.4rem 0;
  border-bottom: 1px solid rgba(0,0,0,0.08);
  transition: padding-left var(--transition);
}

.aside-link:last-child {
  border-bottom: none;
}

.aside-link:hover,
.aside-link:focus-visible {
  padding-left: 0.4rem;
  outline: none;
}

.aside-link-active {
  font-weight: 700;
  padding-left: 0.4rem;
}

/* =====================
   子页卡片区（首页）
   ===================== */
.cards-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 0 2rem;
}

.section-heading {
  font-family: var(--font-pixel);
  font-size: clamp(0.7rem, 2vw, 1rem);
  margin-bottom: 2rem;
  letter-spacing: 0.03em;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card-item {
  animation-fill-mode: both;
}

.card {
  border: var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  background: var(--c-white);
  transition: background var(--transition), color var(--transition), transform var(--transition);
}

.card:hover {
  background: var(--c-black);
  color: var(--c-white);
  transform: translateY(-3px);
}

.card:hover .card-title a,
.card:hover .card-desc,
.card:hover .card-date {
  color: var(--c-white);
}

.card:hover .card-link {
  color: var(--c-white);
  border-bottom-color: var(--c-white);
}

.card-title {
  font-family: var(--font-pixel);
  font-size: 0.55rem;
  line-height: 1.7;
}

.card-title a {
  color: inherit;
}

.card-date {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--c-muted);
}

.card-desc {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--c-muted);
  flex: 1;
}

.card-link {
  font-size: 0.9rem;
  font-weight: 600;
  border-bottom: 2px solid var(--c-black);
  align-self: flex-start;
  transition: border-color var(--transition);
}

/* =====================
   About 快速入口
   ===================== */
.about-nav-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2rem 0 2rem;
}

.about-nav-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
}

.about-nav-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  border: var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.5rem;
  transition: background var(--transition), color var(--transition);
  min-height: 64px;
}

.about-nav-card:hover {
  background: var(--c-black);
  color: var(--c-white);
}

.about-nav-title {
  font-family: var(--font-pixel);
  font-size: 0.5rem;
  line-height: 1.6;
}

.about-nav-arrow {
  font-size: 1.2rem;
  flex-shrink: 0;
  margin-left: 1rem;
}

/* =====================
   页脚
   ===================== */
.site-footer {
  background: var(--c-black);
  color: var(--c-white);
  border-top: var(--border);
  padding: 3rem 1.5rem 1.5rem;
}

.footer-top {
  max-width: var(--max-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(255,255,255,0.2);
}

.footer-brand-big {
  font-family: var(--font-pixel);
  font-size: clamp(1.2rem, 4vw, 2.5rem);
  line-height: 1.3;
  margin-bottom: 1rem;
  letter-spacing: 0.03em;
  color: var(--c-white);
}

.footer-brand-desc {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.65);
  line-height: 1.7;
  max-width: 360px;
}

.footer-links-col nav {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-links-col a {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.75);
  padding: 0.3rem 0;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  transition: color var(--transition);
  min-height: 40px;
  display: flex;
  align-items: center;
}

.footer-links-col a:hover {
  color: var(--c-white);
}

.footer-bottom {
  max-width: var(--max-w);
  margin: 0 auto;
  padding-top: 1.25rem;
  text-align: center;
}

.footer-copy {
  font-size: 0.82rem;
  color: rgba(255,255,255,0.45);
  line-height: 1.6;
}

/* =====================
   Scroll Reveal 动效
   ===================== */
.scroll-reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 500ms ease, transform 500ms ease;
}

.scroll-reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* stagger cards */
.card-item.stagger-item {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 400ms ease, transform 400ms ease, background var(--transition), color var(--transition);
  transition-delay: calc(var(--i, 0) * 80ms);
}

.card-item.stagger-item.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* =====================
   prefers-reduced-motion
   ===================== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
  }
  .scroll-reveal,
  .card-item.stagger-item {
    opacity: 1;
    transform: none;
  }
}

/* =====================
   响应式断点
   ===================== */
@media (max-width: 900px) {
  .hero-inner {
    grid-template-columns: 1fr;
    padding-top: 2.5rem;
  }
  .hero-media {
    order: -1;
    aspect-ratio: 16/9;
  }
  .hero-content {
    align-items: flex-start;
    text-align: left;
  }
  .hero-lead { max-width: 100%; }

  .faq-outer,
  .privacy-outer {
    grid-template-columns: 1fr;
  }

  .faq-aside,
  .privacy-aside {
    position: static;
    order: -1;
  }

  .about-hero-inner {
    grid-template-columns: 1fr;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

@media (max-width: 600px) {
  :root {
    --nav-h: 56px;
  }

  .nav-links a:not(.nav-brand) {
    display: none;
  }

  .cards-grid {
    grid-template-columns: 1fr;
  }

  .about-nav-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: 60vh;
  }

  .hero-title {
    font-size: 0.85rem;
  }

  .page-title {
    font-size: 0.75rem;
  }

  .footer-brand-big {
    font-size: 1.4rem;
  }

  .footer-top {
    grid-template-columns: 1fr;
  }

  .site-main {
    padding: 2rem 1rem 3rem;
  }
}

@media (max-width: 375px) {
  .nav-cta {
    font-size: 0.38rem;
    padding: 0.45rem 0.65rem;
  }
  .hero-inner {
    padding: 2rem 1rem 3rem;
  }
  .page-hero-slim,
  .about-hero,
  .privacy-hero {
    padding: 2rem 1rem 0;
  }
}